The first important exposition in the United States was held in Philadelphia in 1876.
A
暂无解析
AlthoughtheCarbon14methodofdatingoldobjectsisnotfoolproof,itisthebestmethodavailableatpresent
HowmanypeopleareawarethatadancerwiththeNewYorkCityBallettypicallywearsoutaminimumoftwohundredpairsoftoeshoesperyear?
Thewheelsofthefirstroadvehicleswerefashionedfromcrudestonedisks.
Somechildrendisplayanunquenchable难以抑制的curiosityabouteverynewthingtheyencounter.
Despitetheproliferationofotherfastermodesoftransportation,therailroadsremainthelargestcarriersofintercityfreightintheUnitedStates.